Which structure of the hoof will widen with chronic laminitis?

• A. Sole
• B. White line
• C. Frog
• D. Coronary band

Answer: (B)

Chronic laminitis damages the delicate laminae that attach the coffin bone to the hoof wall, allowing the bone to sink and the wall to separate from the sole. This separation occurs at the junction where the hoof wall meets the sole—the white line. As the coffin bone displaces, the space at this junction widens, making the white line visibly broadened. The sole, frog, and coronary band are affected in other ways, but they do not characteristically widen as a result of chronic laminitis.